Anyone really concerned about being limited with 8 GB of RAM? I'm a PC guy by experience and have never experience bottleneck issues with my recent machines (vista, 7) that have had up to 8 GB of RAM. In fact, I barely tap into that resource. Is mac OS a RAM hog? I ordered my iMac with 8 GB with hardly a concern, but it seems a lot of forum users are throwing money in to max-out RAM. On my windows machine, frankly it'd be a waste of money. Thanks.